Hey there! Nice to meet you!
Aside from your recovery phone number, do you have other security information/verification methods, phone, or email address linked to the account?
Did you have two-factor authentication (2FA) active on the account? If yes, do you still have the 25-character recovery codes?
Lastly, may I know when was the last time you successfully signed in to your Microsoft account?
Best regards,
Darhyl